There are a number of medical procedures which require the introduction of medical instruments into arteries and veins. In one such procedure, known as the Seldinger procedure, a surgical opening is made in a vein or artery with a needle. A guide wire is then inserted through the lumen of the needle into the vein or artery. The needle is withdrawn, leaving the guide wire in place. A dilator is then inserted over the guide wire inside an associated sheath. The dilator and guidewire are removed once the sheath is in place. At this point, various types of catheters or leads may be inserted into the vessel within the lumen of the sheath using the sheath as a conduit to prevent damage to the vessel wall.
In conventional procedures, these sheaths often include hemostasis valves. In many cases the hemostasis valve is designed for use with a specific size of a catheter. Such hemostasis valves have been disclosed, for example, in U.S. Pat. Nos. 5,092,857 and 4,909,798.
In medical procedures where a pacemaker lead is inserted into a patient, a sheath is normally used to guide the pacemaker lead to the appropriate location. Before the pacemaker lead is permanently secured in place and attached to a pacemaker, the sheath must be removed. Because of the size of its lumen, the sheath cannot simply slip over the exterior end of the pacemaker lead as that end of the lead contains a connector coupling for connection to the pacemaker.
Accordingly, there have been disclosed a number of sheaths for use in the introduction of pacemaker leads, which can be split in half while still surrounding the pacemaker lead. In this use, once the pacemaker lead is in place, the sheath is longitudinally severed and removed from the pacemaker lead. For example, U.S. Pat. No. 4,983,168 discloses such a layered, peel-away hollow sheath, wherein the sheath wall is comprised of at least two layers, an inside cylindrical layer and an outside layer comprising two semi-cylindrical segments defining opposed axially-directed slits or slots therebetween, which comprise tear lines. U.S. Pat. No. 4,596,559 discloses a tear away sheath for use with a disposable introducer set in conjunction with a catheter. U.S. Pat. No. Re. 31,855 discloses a sheath that has an internal molecular orientation which tears easily in a lengthwise direction and with great difficulty in a crosswise or oblique direction. See also U.S. Pat. No. 4,581,025. Longitudinally scored or perforated sheaths are disclosed in U.S. Pat. Nos. 4,166,469; 4,243,050; 4,345,606 and 4,451,256. A locking dilator for use with peel-away sheaths is disclosed in U.S. Pat. No. 5,098,392.
A problem has developed during the use of these splittable sheaths. During the introduction of a pacemaker lead, a significant amount of bleeding may occur at the operation site, depending upon the blood pressure present in the vessel. Once the sheath is in place within a vessel, it provides a passageway for the free flow of blood away from the operation site.
Further, because of this flow of blood, clotting may occur if the sheath remains in position for an extended period of time. These clots may cause emboli which may pass to the lung and have a detrimental impact on the patent.
These sheaths may also provide a passageway for the introduction of air into the vessel. The inadvertent introduction of air into the blood system can cause air emboli in the patient which may have negative effects.
Because of these problems these splittable sheaths are removed from the theater of operation as soon as possible, even if it would be preferable to maintain them in position for a longer period of time. Such hurried procedures can result in errors or medical complications.
One method of preventing, or at least limiting, the flow of blood out of a sheath while a pacemaker lead is being introduced is for the physician to place his thumb over the exposed end of the sheath or to squeeze or pinch the exposed end of the sheath between his thumb and forefinger. However, neither of these methods for reducing the undesired flow of blood and air through the sheath is desirable, because the opportunity for loss of blood and introduction of air is still present. In addition, the structure of these sheaths still requires the surgeon to hold onto it while it is in place in the vessel, thereby limiting the surgeon's ability to perform other medical procedures at the same time. Moreover, squeezing the exposed end of the sheath can deform or even break the sheath, making lead insertion difficult and increasing the likelihood of damage to the lead as it passes through the sheath. Further, even when holding the end of the sheath or pinching the sheath, flow of blood out of the sheath is not entirely stopped.
Thus, the introduction of a hemostasis valve into a sheath to limit blood flow would be helpful during the introduction of pacemaker leads into the heart and other similar medical procedures. However, because the exterior end of pacemaker leads is larger than the opening in conventional hemostasis valves, it is not possible for pacemaker leads to pass through these conventional hemostasis valves. Accordingly, splittable hemostasis valves contained within splittable sheaths for the introduction of pacemaker leads have been disclosed, for example, in U.S. Pat. Nos. 5,312,355 and 5,125,904. Each of these patents discloses a splittable sheath valve body (16), a splittable sheath valve assembly (14) and a splittable valve membrane (22). To remove the splittable sheath valve assembly (14) from around the pacemaker lead after the lead has been placed within the heart, the splittable sheath valve body (16) and the splittable sheath valve assembly (14) are torn apart along score lines (34, 36) by placing pressure on the flanges (38, 40) of the splittable sheath valve body (16). The splittable valve membrane (22) is also torn apart during this procedure along a weakened line or score line in the splittable valve membrane (22), or, as shown in U.S. Pat. No. 5,312,355, along a Y-shaped cut in the splittable valve membrane (22).
Another valve system incorporated into a splittable sheath for the introduction of pacemaker leads is disclosed in U.S. Pat. No. 5,441,504. A slidable valve (70) secured on a tab (62) of the sheath (40) can be slid to cover the opening in the sheath (40) during introduction of the pacemaker lead. When it is necessary to remove the sheath (40) from the operating theater, the sheath (40) is split along score line (86) with each side of the slidable valve (70) remaining secured to one tab (62) of the splittable sheath (40).
Another splittable sheath containing a splittable valve is disclosed in U.S. Pat. Nos. 5,397,311 and 5,755,693. These patents disclose a valve (30, 30A, 30B or 30C) or a valve system comprising a pair of valves (78, 80) contained within the body of a splittable sheath (18) to prevent the flow of blood through the splittable sheath (18). The valve may comprise a pair of semicircular members, each of which may include a slit, as shown, for example, in FIGS. 7 and 8 of those patents.
An additional splittable sheath system containing a valve that splits is disclosed in U.S. Pat. No. 5,613,953. The valve members (82 and 82A) are part of the handles of the splittable sheath and are separated into separate valve halves by the separation of the exposed handles (90 and 90A) of the splittable sheath. The handles and the valve members are cooperatively connected by a rotatable link assembly (100, 100A) , which is biased into a closed position by integrally formed bias springs.
The devices that have been previously disclosed often have difficulty in being split when used in a medical procedure because of the presence of fluids, particularly blood. In addition, when these prior art devices are split, blood splattering often occurs when the hemostasis valve is torn. Further, the valve often tears unevenly, making it more difficult to remove the splittable sheath and splittable valve. Some physicians are also hesitant to force the tines of leads for pacemakers through these valves because they fear damage to the tines.
In addition, some physicians may want to delay the introduction of a hemostasis valve into the sheath even after the sheath is already in position.
Further, it is sometimes necessary to remove the hemostasis valve from the operating theater at a time when the sheath is still in use.
Thus, it is important to have a device to hold the hemostasis valve which is separate and distinct from the splittable sheath itself.
It is also important to provide an improved partitioned device for holding a partitioned hemostasis valve which can be secured to a splittable sheath and utilized for the introduction of a pacemaker lead into the heart.
Therefore, it is an object of this invention to provide an improved partitioned hemostasis valve system.
It is a further object of the invention to provide a partitioned hemostasis valve system that can be secured to a separate and distinct splittable sheath for the introduction of medical devices into the heart, particularly pacemaker leads.
It is a further object of this invention to disclose a partitioned hemostasis valve system containing an adaptor system for securing the hemostasis valve system to a splittable sheath.
It is a still further object of the invention to disclose a partitioned hemostasis valve system which includes a partitioned hemostasis valve held within a partitioned hemostasis valve housing and a splittable sheath.
It is a still further object of the invention to disclose a partitioned hemostasis valve system which can be secured to a splittable sheath and removed from the splittable sheath without tearing the hemostasis valve.
It is a still further object of the invention to disclose a partitioned hemostasis valve system which includes a partitioned hemostasis valve housing containing a partitioned hemostasis valve and a hemostasis valve separation system.
It is a still further object of the invention to disclose a partitioned hemostasis valve system which includes a partitioned hemostasis valve for use with a splittable sheath which can be removed from a position of surrounding an electrode lead without tearing the splittable sheath.
It is a still further object of the invention to disclose a partitioned hemostasis valve system enclosed within a partitioned hemostasis valve housing, which housing can be locked in a closed position and unlocked in an open position.
It is a further object of the invention to disclose a partitioned hemostasis valve housing containing pivotable wing portions which force the separate sides of a partitioned hemostasis valve together.
It is a still further object of the invention to disclose a partitioned hemostasis valve system which includes a partitioned hemostasis valve formed from a pair of hemostasis valve sections joined together by an extended seal.
These and other objects and features of the present invention will become apparent to those skilled in the art from a consideration of the following detailed description and claims. The description, along with any drawings, provides a selected example of the construction of the device to illustrate the invention.